On Saturday, September 27, 2014 01:32:59 PM Wang Weidong wrote:
> On 2014/9/27 7:21, Rafael J. Wysocki wrote:
> > On Thursday, August 21, 2014 01:55:15 PM Wang Weidong wrote:
> >> As the initialized freq_tables maybe different from the p-states
> >> values, so the array index is different as well.
> >>
> >> p-states value: [2400 2400 2000 ...], while the freq_tables:
> >> [2400 2000 ... CPUFREQ_TABLE_END]. After setted the freqs 2000,
> >> the perf->state is 3 while the freqs_table's index should be 2.
> >> So when call the get_cur_freq_on_cpu, the freqs value we get
> >> is 2400.
> >>
> >> So, fix the problem with the correct tables.
> >
> > What you're saying is basically that freq_table and perf->states
> > diverge at one point. Shouldn't we re-generate freq_table in that
> > case instead of fixing up get_cur_freq_on_cpu() only in a quite
> > indirect way?
> >
> Hi Rafael,
>
> Thanks for your reply.
>
> You mean that we should re-generate the freq_table in that case?
> Could we fix the table init like this:
>
> --- a/drivers/cpufreq/acpi-cpufreq.c
> +++ b/drivers/cpufreq/acpi-cpufreq.c
> @@ -779,7 +779,7 @@ static int acpi_cpufreq_cpu_init(struct cpufreq_policy
> *policy)
>
> /* table init */
> for (i = 0; i < perf->state_count; i++) {
> - if (i > 0 && perf->states[i].core_frequency >=
> + if (i > 0 && perf->states[i].core_frequency >
> data->freq_table[valid_states-1].frequency / 1000)
> continue;
>
> when the value is same, we just keep the value into the freq_table.
That would only be OK if it is guaranteed that the set of available
states hasn't changed, which I'm not sure is the case.
Rafael
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